Explain two-phase locking protocol, Operating System

Q. Show that a few schedules are possible under the two-phase locking protocol however not possible under the timestamp protocol and vice versa.

Answer: A schedule that is authorized in the two-phase locking protocol but not in the timestamp protocol is:

1660_Explain Two-phase locking protocol.png

This schedule isn't allowed in the timestamp protocol because at step 7 the W-timestamp of B is 1.

A schedule that is permitted in the timestamp protocol but not in the two-phase locking protocol is:

2316_Explain Two-phase locking protocol1.png

This schedule can't have lock instructions added to formulate it legal under two-phase locking protocol because T1 must unlock (A) between steps 2 and 3 and must lock (B) between steps 4 and 5.

Posted Date: 7/27/2013 3:54:00 AM | Location : United States







Related Discussions:- Explain two-phase locking protocol, Assignment Help, Ask Question on Explain two-phase locking protocol, Get Answer, Expert's Help, Explain two-phase locking protocol Discussions

Write discussion on Explain two-phase locking protocol
Your posts are moderated
Related Questions
Q. Illustrate the function of Loader? A loader is a routine which loads an object program and prepares it for execution. There are many loading schemes: relocating, absolute an

Question: a) The following questions pertain to User and Group accounts in Windows XP: i) Give four differences between a Power User and a Guest User account. ii) Explain h

Define lazy swapper. Rather than swapping the entire process into main memory, a lazy swapper is used. A lazy swapper never swaps a page into memory unless that page will be ne

How can the deadlock be prevented-Safe State Safe state : A state is safe if the system is able to allocate resources to each process in some order and still avoid deadlock.

What are the phases of background processing? Phases are:- Job Scheduling. Job Processing. Job Overview.

Describe the technique of packing. The physical record size will not accurately match the length of the desired logical record and the Logical records may even differ in length

BENEFITS OF THREADS OVER PROCESS If implemented correctly after those threads have some advantages of (multi) processes, they take: 1. Less time to create a new thread tha

what is deadlock


Define the DosExit Function used in the OS/2 DosExit(action, resultCode)  DosExit function is to be called when a thread or process is finished executing. If EXIT_THREAD is